Feature request, resolver parameter to allow mix of local and remote resolving.

### Expected Behaviour
Lets say I have some schemas locally that I don't have on the server yet.

`jsonschema2md -d schemas -r "https://hai.ai/schemas/=schemas/"`

### Actual Behaviour
`cannot resolve https://hai.ai/schemas/components/tool/v1/tool.schema.json`

`jsonschema2md -d schemas -i schemas` also fails because of not resolving the base schemas in a doc with an $id like "$schema": "http://json-schema.org/draft-07/schema#",

Would love a way to detect a prefix in a resolver for some files, but not all (as with -i)

Start by reproducing the two examples with jsonschema2md using -d, -r, and -i, focusing on how resolver prefixes handle local and remote schemas. Done means a resolver can apply a local mapping for matching files while continuing remote resolution for others, including base schemas identified by $id.

Written by the indexing model from the issue text.